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Title: Acoustic emission monitoring of crack propagation in additively manufactured and conventional titanium components

Abstract

We report that additive manufacturing (AM) is a novel and innovative production technology that can produce complex and lightweight engineering products. In AM components, as in all engineering materials, fatigue is considered as one of the principle causes of unexpected failure. In order to detect, localise and characterise cracks in various material components and metals, acoustic emission (AE) is used as a non-destructive monitoring technique. One of the main advantages of AE is that it can be also used for dynamic damage characterisation and specifically for crack propagation monitoring. In this research, we use AE to monitor the fatigue crack growth behaviour of Ti6Al4V components under four-point bending. The samples were produced by means of AM as well as conventional material. Notched and unnotched specimens were investigated with respect to the crack severity and crack detection using AE. The main AE signal parameters –such as cumulative events, hits, duration, average frequency and rise time– were evaluated and indicate sensitivity to damage propagation in order to lead to a warning against the final fracture occurrence. Finally, this is the first time that AE is applied in AM components under fatigue.

Authors:
ORCiD logo [1];  [1];  [1];  [1]
  1. Vrije Universiteit Brussel (VUB), Brussels (Belgium)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1415387
Report Number(s):
LA-UR-17-24367
Journal ID: ISSN 0093-6413
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Mechanics Research Communications
Additional Journal Information:
Journal Volume: 84; Journal Issue: C; Journal ID: ISSN 0093-6413
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING; Acoustic emission; Fatigue; Additive manufacturing; Crack propagation; Titanium

Citation Formats

Strantza, Maria, Van Hemelrijck, Danny, Guillaume, Patrick, and Aggelis, Dimitrios G. Acoustic emission monitoring of crack propagation in additively manufactured and conventional titanium components. United States: N. p., 2017. Web. doi:10.1016/j.mechrescom.2017.05.009.
Strantza, Maria, Van Hemelrijck, Danny, Guillaume, Patrick, & Aggelis, Dimitrios G. Acoustic emission monitoring of crack propagation in additively manufactured and conventional titanium components. United States. doi:10.1016/j.mechrescom.2017.05.009.
Strantza, Maria, Van Hemelrijck, Danny, Guillaume, Patrick, and Aggelis, Dimitrios G. 2017. "Acoustic emission monitoring of crack propagation in additively manufactured and conventional titanium components". United States. doi:10.1016/j.mechrescom.2017.05.009.
@article{osti_1415387,
title = {Acoustic emission monitoring of crack propagation in additively manufactured and conventional titanium components},
author = {Strantza, Maria and Van Hemelrijck, Danny and Guillaume, Patrick and Aggelis, Dimitrios G.},
abstractNote = {We report that additive manufacturing (AM) is a novel and innovative production technology that can produce complex and lightweight engineering products. In AM components, as in all engineering materials, fatigue is considered as one of the principle causes of unexpected failure. In order to detect, localise and characterise cracks in various material components and metals, acoustic emission (AE) is used as a non-destructive monitoring technique. One of the main advantages of AE is that it can be also used for dynamic damage characterisation and specifically for crack propagation monitoring. In this research, we use AE to monitor the fatigue crack growth behaviour of Ti6Al4V components under four-point bending. The samples were produced by means of AM as well as conventional material. Notched and unnotched specimens were investigated with respect to the crack severity and crack detection using AE. The main AE signal parameters –such as cumulative events, hits, duration, average frequency and rise time– were evaluated and indicate sensitivity to damage propagation in order to lead to a warning against the final fracture occurrence. Finally, this is the first time that AE is applied in AM components under fatigue.},
doi = {10.1016/j.mechrescom.2017.05.009},
journal = {Mechanics Research Communications},
number = C,
volume = 84,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on May 31, 2018
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